[Chicopower]

Same result here.
The HDR toggle switch is no more present in kodi settings UI and, like previous versions, HDR infos are not sent to my tv in this latest version.
But, this latest version have a better behaviour for a "not active hdr tv". By default, we are now able to set Tone Mapping settings (hdr tone mapping workaround).

Logs on my side:
...
Display HDR capable is detected and Windows HDR switch is OFF
...
DX:: DeviceResources::IsHDRDisplayEnabled: Monitor is HDR capable although is NOT enabled.
...
DXVA:: CProcessorHD::InitProcessor: video processor supports HDR10.
...

But, with the great Kodi documentation, i'm now able to build and deploy some code change on my side (based on your current branch).
I tried some little things, but nothing fixed the HDR problem on my side at this moment.
For sure, i will continue to try some things on my side

My next steps to "help Kodi" is to continue reading this thread, provide some testing help asked here, reading documentation here and trying some code change on my side.
Thx